MBS says he is satisfied with Riyadh conference despite boycott by politicians and businesses over Khashoggi killing.

Saudi Crown Prince Mohammed bin Salman (MBS) has briefly attended a high-profile economic forum in Riyadh that was boycotted by global business chiefs and politicians after the killing of journalist Jamal Khashoggi.

Many in the audience of over 2,000 clapped or cheered as the prince, the kingdom's de facto ruler, entered the main hall on Tuesday, smiling as he sat down next to Jordan's King Abdullah II.

The 33-year-old arrived at the forum late in the day after attending a meeting at which his father, King Salman, received members of Khashoggi's family, including the journalist's son Salah.

MBS said he was "satisfied" with the Future Investment Initiative as he toured the venue.

"Great, more people, more money," the crown prince told reporters.

He left shortly afterwards, without delivering a speech.

Organisers said he is expected to participate in a panel on Wednesday.

Davos in the desert

The three-day conference, a brainchild of MBS, is the kingdom's first major event since Khashoggi's killing at the Saudi consulate in Istanbul earlier this month.

Critics of the crown prince suspect he ordered the killing, or at least had knowledge of it - a claim denied by Saudi officials.

The Saudi cabinet has promised to hold to account those who were responsible for Khashoggi's death and those who "failed in their duties" in the case that has provoked an international furore and strained ties between Riyadh and its international allies.

Khashoggi, a critic of MBS, vanished after he entered Saudi Arabia's consulate in Istanbul on October 2.

After first denying any involvement in his disappearance, Riyadh said on Saturday Khashoggi died during a fight in the consulate. Later, a Saudi official attributed the death to a chokehold.

Many foreign investors see a risk that the Khashoggi case, which drew global condemnation, could damage Riyadh's ties with Western governments.

US Treasury Secretary Steven Mnuchin and senior ministers from Britain and France pulled out of the event along with chief executives or chairmen of about a dozen big financial firms, such as JP Morgan Chase and HSBC, and International Monetary Fund chief Christine Lagarde.

Uber CEO Dara Khosrowshahi, who also withdrew from the event, said the firm was awaiting the full facts on Khashoggi's case before deciding whether that would affect Saudi involvement in the ride-hailing service.

At the opening of the conference, Energy Minister Khalid al-Falih acknowledged "these are difficult days".

"We are going through a crisis," al-Falih said in his speech. Calling Khashoggi's murder regrettable, he said: "nobody in the kingdom can justify it."

He also heaped praise on the CEO of French energy giant Total, Patrick Pouyanne, for standing by Saudi Arabia.

"We see what partnership means when you have difficult times," Pouyanne responded as he shared the stage with al-Falih.

"This is when you really strengthen a partnership."

Several other Western banks and other companies, fearful of losing business such as fees from arranging deals for Saudi Arabia's $250bn wealth fund, sent lower-level executives even as their top people stayed away.

Meanwhile, Dmitriev, the head of Russia's Direct Investment Fund, said Khashoggi's killing needed to be investigated and the culprits punished, but that the Saudi drive for economic and social reform could not be ignored.

"Saudi Arabia's reforms are important and they are worth supporting," he told Reuters news agency.

Top executives of Asian firms have also been hesitant to pull out, so the participation of Chinese and Japanese institutions may help Riyadh claim the three-day conference as a success.

"I think this conference will open the gateways to Asian and Russian investment in the Saudi economy regardless, irrespective if the crisis gets resolved or not," Ayham Kamel of Eurasia Group told The Associated Press.